In one aspect this invention relates to cargo retaining systems. In a further aspect this invention relates to the clamps attached to a cargo trailer for use with cargo tie-down straps or chains.
The trailers used in trucking generally consist of a flat platform made of wood or metal surrounded by a frame of box beams having a hollow interior, the platform being mounted on a number of axles.
To hold loads in place and prevent cargo slippage, tie-down straps or chains are attached to the frame of the trailer and either attached to the load or another point on the frame and sufficient tension applied to the tie-down to prevent cargo motion. The tie-downs are generally attached to some form of tie-down ring or anchor which is firmly attached to the frame.
The simplest form of a tie-down device is a ring which is permanently exposed above the frame member. While providing a simple inexpensive tie-down anchor, such an anchor is permanently exposed to cause damage or be damaged even when not needed. One example of a permanently exposed ring is U.S. Pat. No. 2,688,504 which discloses a ring with a T-shaped foot which can be mounted within a complimentary channel fastened to the trailer.